Slice the lemon and garlic. Separate leaves of radicchio.
Simmer the broth with pepper, salt, thyme, garlic, and lemon over medium-low heat.
Fry bacon, then remove bacon from the pan. Save the fat for cooking the halibut.
Add the clams and radicchio to the broth. Cook for about 15 min. until the clams open. Discard the clams that did not open.
Season both sides of the fish with salt and freshly-cracked pepper. Brown both sides of the halibut in the bacon fat. Cook the first side for 4 – 5 min., then turn over. Place butter on the fish. Cook the other side for 3 – 4 min.
Add clams, radicchio, and bacon to each soup bowl. Place a piece of halibut on top and pour broth over it. Garnish with parsley. Serve with bread.